[Long-term anticoagulant therapy in subjects over 75 years of age. 100 cases]

100 patients (median age 79 years) were given anticoagulant therapy (ACT) for a period of time averaging 5 years 3 months (522 follow-up years).--Out of 3 522 Quick tests, converted into prothrombin times and all carried out in the same laboratory, the prothrombin time was at or less than 32% in 60.5%, and 34% in 69.6% of the tests.--The mean therapeutic doses were less than 27% of those for adults, and were decreased by 3 mg of phenindione per year over the age of 75, only the actively treated cases being retained.--The risks are the same as those for the middle-aged adult. They depend more on the quality of the investigations than upon age. In the group which has been studied, slight or frank haemorrhagic complications (0.05/year/patient) were the result of a demonstrable overdosage in only one case in four. They were not responsable for any deaths in this series.--because of the referral patterns, the patients studied consisted of 79 with ischaemic heart disease, 27 with peripheral vascular disease, 9 cerebrovascular accidents, and 6 with thrombo-emoblic problems, not counting the 23 complications during the course of the study. In those patients with ischaemic heart disease, well-regulated anticoagulant treatment was associated with a favourable clinical course, and the correlation was significant.--there is not argument against the administering of a full and prolonged course of ACT to a patient of more than 75 years of age.